Nested if/else statement inside for loop not working as expected

I cannot spot where my mistake is on my IF/ELSE statement nested inside my for loop. I did try to use a while loop to get make my IF/ELSE statement work, but it didn't work as expected.

Even my Console.Writeline statement cannot capture the right price and size.

My code:

static void Main(string[] args)
{
    string[] size = { "S", "M", "L", "X"};
    decimal[] price = { 6.99M, 8.99M, 12.50M, 15.00M};

    Console.WriteLine("Please enter a pizza size : ");
    string pizzaSize = Console.ReadLine();

    int i;

    for (i = 0; i < size.Length; i++)
    {
        if (size[i] == pizzaSize)
        {
            Console.WriteLine("Your pizza size is " + pizzaSize + ". The price is " + price[i].ToString("C"));
        } else
        {
            Console.WriteLine("Please enter a valid pizza size");
            return;
        }
    }
    Console.ReadKey();
}